See Pyure's answer1. What is inflation? I previously called this a trick question.
Money is still balanced against the reserves of gold that a country owns, see "gold standard"2. What is money? We are no longer on a precious metal standard.
I assume you are talking about a general view of what is healthy in terms of money flow.3. What is the proper view of money flow?
Governments always try to encourage public spending as it keeps an economy stable. If people don't spend money, then the value of products go down. And if the value of products go down, the people making the products get less money. If the people making the products make less money, they can't afford to buy more raw materials. If they can't afford to buy more raw materials, the cost of raw materials either has to drop to accommodate this, or the supplier has to do something drastic.
Let's take cheese (because it is an easy example)
People stop buying cheese as much, for whatever reason.
Which means that instead of 1kg of cheese being worth $10, it is now worth $6.
That means that cheese companies are making 40% less than usual, so either they have to reduce the employees' wages, or have to sack some off. OR they have to try and get the milk they use to make the cheese for less, and because of the size of cheese industry, you need to have all the employees, and you don't lower their wages in fears of strikes/mass quittings. So you bargain for cheaper milk.
Now the farmer who usually only gets $2 for every kg of milk (in its equivalence to cheese) only gets $1.50. And because he is getting 1/4 less cash, he has to get rid of a quarter of his cows, so he can afford to at least keep some cows alive.
Instead of just killing his cows, he sells them off for beef, because it is a little bit extra money for him. But that means that the amount of beef produced that month goes up, which means its cost goes down...
And this continues throughout, so the flow of money doesn't want to change too much, or else it can cause MASSIVE ripples in the market.
No, of course not. Rich people make a lot of money, but also pay a lot in taxes and general spending, which helps keep the economy going.4. Is there any problem with a person being rich?
That's what pension schemes are for. A person works, and puts a small percentage of their wage away for when they retire. And when they do, they may have $400,000 saved up, which on $20,000 a year is 20 years. Which is 10 years over the average life expectancy (in most countries).5. How do you deal with someone working for 40 years, and then retiring and living another 40-60 years?
But living more than 40 years past retirement age is rare, seeing as the OLDEST a person can be when they are "forced" to retire is in their early-mid 60's (at least here in the UK) and 40 years is pushing the 100's.
If someone retires when they have they are in their 40's/50's they can almost definitely afford to live until they are 100 (if you retire "young" you are most likely a million/billionaire)